It's the second year in a row that Lone Pine came in first on the report, which is based on discussions with the funds themselves, audited reports issued by the firms and confidential sources, Bloomberg noted in a story about the report.

The ranking generally includes a manager's own investment in his firm.

Neighboring firms Lone Pine was founded in 1997 by Greenwich resident Stephen Mandel, now 57, who had previously worked at Julian Robertson's legendary long-short and stock-picking hedge-fund firm Tiger Management.

Halvorsen, a Norway-native who lives in Darien, also worked at Tiger before he launched Viking Global in 1999.

Today, the two "Tiger Cub" fund managers are working on opposite sides of Greenwich's main train station.

Lone Pine is located on the second floor of Two Greenwich Plaza, the big, boxy and dark-glass commercial space standing just south of the train station. Viking Global is just north of the station, at 55 Railroad Ave.

Both Mandel and Halvorsen declined to comment for this story.

Good picking

Overall, the $2.5 trillion hedge fund industry struggled in 2013, returning an average of about 9.3 percent, according to the Chicago-based Hedge Fund Research Inc. That trailed the Standard & Poor's 500 Index's climb of 30 percent. It was the fifth straight year in which the stock index outperformed the hedge fund industry.

As a result, many observers have been critical that hedge funds continue to charge high fees -- as much as 2 percent of all assets under management and 20 percent of all returns; or in rare cases, even more -- while producing such lackluster returns. Still others have countered that hedge funds are designed, in principle, to be uncorrelated to wider markets -- which makes it hard to keep pace with a surging bull market.

Even so, Lone Pine and Viking Global got ahead with winning bets on stocks that outperformed.

Lone Pine achieved big gains with such stocks as Michael Kors, 21st Century Fox, Valeant Pharmaceuticals, Visa and FleetCor Technologies, according to the firm's Securities and Exchange Commission filing for the quarter that ended last Sept. 30.

In 2013, Lone Pine's funds returned 22 percent, net of management but not performance fees. Its long-only fund, Lone Cascade, was up 32 percent, according to Institutional Investor.

Meanwhile, Viking Global won big with stocks like Capital One Financial, Thermo Fisher Scientific, Time Warner and Valeant Pharmaceuticals, among others. Halvorsen's long-short fund, Viking Global Equities, was up 23 percent. His Viking Long Fund was up 38 percent, according to Institutional Investor.

In November, his Stamford-based SAC Capital pleaded guilty to fraud charges stemming from insider trading by its employees and was forced to return all outside investor money. Nevertheless, SAC generated $2.6 billion in profits over the year, Institutional Investor reported.